The invention relates to a pallet container having a thin-walled plastic container for liquid or flowable substances, including a steel-mesh cage of horizontal and vertical rods tightly enclosing the plastic container, thus forming a support cage, and a floor pallet on which the plastic container is seated and to which the steel-mesh support cage is permanently attached.
A pallet container of this type, having a steel-mesh support cage for the inner, thin-walled plastic container is known from DE-B-30 39 635. The steel-mesh support cage is fastened to the floor pallet--a commercial pallet of wood, for example--by means of cramps, clamps or claws across the very bottom horizontal rod. The cramps or clamps may be nailed (riveted) or screwed to the top plate of the pallet.
Another pallet container that is well-known (EP-A-0 438 718) has the individual pallet elements of wood connected by flat steel elements across them at an suitable distance above them (for the use of the lifting forks of a forklift vehicle). The support cage, its very bottom includes a horizontal rod which is fastened to the floor pallet by means of sheet steel brackets welded to the flat steel elements.
The pallet containers must pass official approval procedures meeting certain quality criteria so that they can be used in industry. For example, internal pressure testing and drop testing from specific drop heights with the pallet containers filled are carried out. The most unfavourable case is a diagonal drop to the lower pallet face, where the bottom discharge valve of the inner plastic containers is located.
Drop testing of this type showed that the inner container, when it hits the ground, will attempt to shift against the floor pallet due to the kinetic energy; at the same time, the fastening brackets of the cage shell are torn off the floor pallet in other areas of the circumference also. Therefore, the fastening of the lower edge of the steel-mesh support cage to the pallet is a significant weak point. As the steel-mesh support cage is fixed only at a few points, the steel mesh is deformed and distorted very unevenly; part of the weldment joints at the mesh intersections will tear apart, and free rod ends may damage the thin-walled plastic container.